medical Definition of bornavirus
: a single-stranded RNA virus (family Bornaviridae) that has a spherical virion with a lipoprotein envelope and chiefly infects the central nervous system of birds and mammals (such as sheep, dogs, and horses) causing mild to fatal disease
- Bornaviruses, a group of RNA viruses that cause disease in horses and sheep, first inserted their genetic material into ancestral human DNA at least 40 million years ago …
- —Tina Hesman Saey, Science News, 30 Jan. 2010
